The present invention relates to a cold storage in which a cooling unit constituted of a compressor and an evaporator is incorporated below an insulating box having a storing chamber disposed therein.
The cold storage of this type conventionally used as a low-temperature showcase comprises a machine chamber disposed below the storing chamber in the insulating box, and a cold air outlet and a cold air inlet formed in a bottom wall of the insulating box to communicate with the inside of the machine chamber. In the machine chamber, a cooling box having an opening in its upper surface is disposed to abut on the bottom wall of the insulating box. In the cooling box, an evaporator and a blower for the evaporator constituting a cooling unit are arranged. The inside of the storing chamber and the cooling box are communicated with each other via the cold air inlet and the cold air outlet. Below the cooling box of the machine chamber, a compressor, a condenser, a blower for the condenser, and the like constituting the cooling unit together with the evaporator are installed on a mounting base equipped with casters for movement on its bottom surface, thereby constituting a well-known refrigerant circuit.
The cooling box is disposed on the mounting base, and detachably attached to the bottom wall of the insulating box. The cooling box, the evaporator, the blower for the evaporator, the compressor, the condenser, and the like can be freely taken in/out of the machine chamber together with the mounting base by using the casters, and the cooling unit can be separated from the insulating box (e.g., see Japanese Patent Application Laid-Open No. 2000-105058).
However, with the aforementioned configuration, cold air leaks from a space generated between the upper surface opening of the cooling box and the cold air outlet or inlet, necessitating lifting of the cooling box including the evaporator and the blower for the evaporator therein and its fixing to the bottom wall of the insulating box by fixtures after the mounting base is received in the machine chamber. Thus, there is a problem of complex attaching work of the cooling unit. In this case, the cooling box must be fixed in positions corresponding to the cold air inlet and the cold air outlet formed in the bottom wall of the insulating box, making positioning difficult. Thus, there is a problem of more deteriorated workability.
Conventionally, therefore, a mechanism has been developed in which a suspension rail is disposed in a bottom wall lower surface of an insulating box, a support rail is disposed on a side face of a cooling box fixed to a mounting base, and a cooling unit is lifted to the bottom wall side of the insulating box in a suspended state of the support rail from the suspension rail. With this mechanism, however, a large structure such as the suspension rail must be added on the bottom wall side of the insulating box in accordance with sizes of various machines, reducing versatility to cause a cost increase and a problem of securing a space in a machine chamber.